4 ms·
Parallel Algorithm Leads to Crypto Breakthrough
- cperciva 17y agoOk, I understand the "parallel algorithm" bit... but where's the "crypto breakthrough"? Breaking 56-bit DES? That was old news over a decade ago.
- redmage 17y agoI think their point was this: When using a Pico FPGA cluster, however, each FPGA is able to perform 1.6 billion DES operations per second. A cluster of 176 FPGAs, installed into a single server using standard PCI Express slots, is capable of processing more than 280 billion DES operations per second. This means that a key recovery that would take years to perform on a PC, even with GPU acceleration, could be accomplished in less than three days on the FPGA cluster. So, they managed to brute-force DES a lot faster. No crypto breakthrough, please move along. :) This should have been titled "FPGA cluster brute-forces DES in record time" or something like that.
- patrickgzill 17y agoClearly the NSA has had such capabilities for a long, long time now.
- redmage 17y agoSure, but I suppose their means didn't consist in a PCI Express card filled with FPGAs, like described in the article.
- cperciva 17y agoFPGA cluster brute-forces DES in record time Even that isn't true. Deep Crack took 56 hours (matching the "less than three days" claimed in the article), while the combined Deep Crack + Distributed.Net effort took less than 24 hours.
- redmage 17y agoSorry, my bad. I didn't bother to research, just pulled that from the article. Pico Computing has announced that it has achieved the highest-known benchmark speeds for 56-bit DES decryption, with reported throughput of over 280 billion keys per second achieved using a single, hardware-accelerated server.
- cperciva 17y agoOk, so 12 years after Deep Crack they've managed to get triple its performance. I can't say that I'm very impressed.
- redmage 17y agoWhat can I say? Pico Computing likes to brag and Dr. Dobb's published an article about it. As you said in your first comment, there's nothing new about this.
- sp332 17y agoDeep Crack used specialized ASICs. The breakthrough is that these general-purpose (reprogrammable) FPGAs are actually faster.
- deleted 17y ago[deleted]
- NateLawson 17y ago1998's DES cracker implemented on today's FPGAs is faster. There is no algorithmic advance -- this is just a thinly-disguised ad for their particular FPGA card. Moving right along...
- CWuestefeld 17y agoI've often wondered how you know when you've actually found the solution. The massively parallel algorithm iteratively decrypts fixed-size blocks of data to find keys that decrypt into ASCII numbers. This technique is often used for recovering the keys of encrypted files containing known types of data. This doesn't make sense to me. I mean, what if I didn't encrypt ASCII numbers? What if it's, say, an email message that's predominantly text in, say, UTF-8 or UTF-16? And it seems to me that as we develop richer ways to encode data, it also makes it correspondingly difficult to decrypt that data.
- moron4hire 17y agoNot sure about UTF-16, but UTF-8 is backwards compatible with ASCII. A lot of decryption requires having a general idea of what the message contains. If you know that the message is standard English text, then that gives you huge opportunities, like finding keys that make parts of the message decrypt to the word "the".
- cperciva 17y agoThe field of cryptography developed in the context of nation-state actors and idiots who use crypto wrong. (Come to think of it, not much has changed.) In WW2, a lot of crypto was broken thanks to known plaintexts -- e.g., "Today's weather is..." -- or chosen plaintexts -- e.g., "Submarine sighted at...". This was made easier, of course, by the fact that military structures tend to use very consistent communications formats. You're quite right that you can slow down a brute force attack by making the input data hard to recognize -- one trivial approach is to pad it to a large size and then apply an all-or-nothing transform -- but by the time this sort of mechanism was feasible, brute force key searches stopped being useful due to increased key lengths.
- eru 17y agoAs far as I know the allies used to spot the plaintext word "EINS" in the Enigma ciphertexts. This was helped by the omission of numbers --- or anything besides letters --- from the Enigma's alphabet. They did not even have a space key.
- jacquesm 17y agoThat's running 10 times faster than this rig: http://www.copacobana.org/ http://www.copacobana.org/ And it cracked DES in about 9 days iirc, @35 billion keys / second.